Digital projections by Yael Braha animated the rear wall at Orchestra Hall during a latenight concert by the Minnesota Orchestra conducted by Courtney Lewis. Photo by Claude Peck

If Minnesota Orchestra wants to attract younger audience members, it would be smart to plan more concerts like the one held at Orchestra Hall on Saturday night.

The crowd for the free 10 p.m. show -- a tie-in event of Northern Spark's all-night rain-and-art fest -- nearly filled the main level of the hall, and the concertgoers appeared a good three or four decades younger, overall, than the audience for most classical concerts by the orchestra.

Longtime subscribers heard a show at 7 p.m. featuring the Mahler 5 and a Kevin Puts symphony, his number 4. (That show is reviewed here.) The Puts alone was repeated at 10 p.m. in a 30-minute concert that also included a sophisticated ive digital projection on the hall's back wall by artist and filmaker Yael Braha and Bryant Place.

The just-turned-30 conductor was Courtney Lewis, who is leaving Minnesota for posts in New York City and Jacksonville, Fla.

The full orchestra performed the Puts symphony, and they still wore their black outfits and tuxedos from the earlier concert. But the mood was much more relaxed than usual, with people taking cellphone photographs and late arrivers filing in. Neither of these "distractions" was any kind of major distraction.

A few people commented afterward that the music was cinematic enough that they did not need the added projections, but most people said they loved the combination. Braha used the familiar tumbling-dice back wall to good effect, with projections that seemed to spiderweb between them and to outline them and "fill" the cubes with dots and orbs in a state of color and motion. Only occasionally did the rear wall become a flat screen for larger, overall moving images, including one that resembled wind-whipped prairie grasses seen from a great height.

The fact that Braha was doing it "live" was demonstrated when the system crashed briefly and had to be rebooted. Lewis tried to hush the applauding crowd and sought the thumbs up from the back of the hall to restart the music.

Puts is a contemporary composer unafraid of writing lush pages for the string section, or of giving a piece some tutti crescendos. His full-throated, brass-heavy ending brought multiple standing ovations from the young crowd. A nervous looking Braha took several bows alongside Lewis and the musicians.

The night was far from over at 10:30 p.m., as bands were programmed into the off-lobby room until 3 a.m.